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    <title>h_inf_st</title>
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    <center>Scilab Function</center>
    <div align="right">Last update : 13/01/2005</div>
    <p>
      <b>h_inf_st</b> -  static <tt>
        <b>H_infinity</b>
      </tt> problem</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>[Kopt,gamaopt]=h_inf_stat(D,r)  </tt>
      </dd>
    </dl>
    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>D</b>
        </tt>: real matrix</li>
      <li>
        <tt>
          <b>r</b>
        </tt>: 1x2 vector</li>
      <li>
        <tt>
          <b>Kopt</b>
        </tt>: matrix</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
    computes a matrix <tt>
        <b>Kopt</b>
      </tt> such that largest singular value of:</p>
    <p>
      <tt>
        <b>lft(D,r,K)=D11+D12* K*inv(I-D22*K)* D21</b>
      </tt>
    is minimal (Static <tt>
        <b>H_infinity</b>
      </tt> four blocks problem).</p>
    <p>
    D is partionned as <tt>
        <b>D=[D11 D12; D21 D22]</b>
      </tt>
    where <tt>
        <b>size(D22)=r=[r1 r2]</b>
      </tt>
    </p>
    <h3>
      <font color="blue">Author</font>
    </h3>
    <p>F.D. ;   </p>
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